Researchers have developed an effective field theory (EFT) describing the interactions of scalar glueballs, exotic particles composed solely of gluons, the carriers of the strong force. This new framework, based on the Yang-Mills gluon condensate, allows for the calculation of fundamental properties of these particles, such as their interaction radius, and establishes a systematic bridge between effective field theories and first-principles lattice Quantum Chromodynamics (QCD) calculations.

The theory starts from a coherent-state formulation of the Yang-Mills vacuum and derives an effective Lagrangian for the scalar glueball and its interactions with gluons. A key result is the prediction of an effective interaction radius for the ground-state scalar glueball, identified with the f₀(1710) resonance, of rᵢₙₜ = 0.28 fm. This value shows excellent agreement with recent lattice QCD determinations, which yield a mass radius of 0.263(31) fm. The momentum dependence of the normalized form factor is also consistent with lattice QCD gravitational form factor data.

The inclusion of the first excited 0⁺⁺ glueball state introduces modest corrections to the interaction radius, resulting in rᵢₙₜ* = 0.240 fm, while producing stable and kinematically robust modifications of the form factor. This advance provides a robust theoretical tool for better understanding the dynamics of glueballs, particles whose existence is predicted by QCD but are challenging to observe experimentally due to their unstable nature and mixing with conventional mesonic states. The agreement with lattice calculations strengthens the validity of this EFT approach.